Precision 5520 Ram Maximum speed support

I want to upgrade my precision 5520 so I have to make sure if my laptop can support 2666Mhz ddr4 ram (corsair vengeance 16GB x2 2666MHz). If it can so will it works with full speed or just 2400Mhz? I’m using two 16gb 2400Mhz rams so is there any difference in speed if I replace them with 2666Mhz ones? Hope someone can help me, thanks 

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